Collimating apparatus for aligning prism-type binoculars



Sept. '6, 1938. w, 0, HAMMER 2,129,130

COLLIMATING APPARATUS FOR ALIGNING PRISM-TYPE BINOCULARS Filed April 28, 1937 INVENTOR. VV/LL/A M O. HAMMER ATTORNEY.

Patented Sept. 6, 1938 UNITED STATES PATENT OFFICE COLLIMATING APPARATUS FOR ALIGNING PRISM-TYPE BINOCULARS William 0. Hammer, San Francisco, Calif.

Application April 28, 1937, Serial No. 139,348

11 Claims.

This invention relates to the adjustment of the optical systems of binocular field or opera glasses of the type which are provided with a longitudinal pivotal or hinged joint between the two barrels for adjusting them to various eye separations, and particularly to such binoculars which are provided with offset barrels fitted with sets of prisms for giving a much larger image with a shorter instrument.

The principal object of the invention is to provide apparatus which will facilitate collimation of the optical systems of the two barrels of such binoculars.

A further object of the invention is to provide such apparatus which will be adaptable for all sizes and types of such binoculars.

Another object is to provide such apparatus which may be very quickly operated.

Another object is to provide a system of aligning the lens systems of such binoculars with the pivotal joint of the instrument without requiring the removal of any of its lenses or substitution of other lenses.

Still another object is to provide an apparatus for the purpose set out which will dispense with the insertion of any hair lines into the binoculars to aid in the aligning operations.

Other features of the invention reside in the details and construction whereby the invention is carried out and made practical, all as will appear in the following description and accompanying drawing.

In the drawing:

Figure l is a perspective View of the apparatus shown with a pair of prism type binoculars in position for testing and adjustment;

Figure 2 is an enlarged elevation of the special centering bull's-eye and hair cross line plate of the collimator tubes;

Figure 3 shows a modified form of the bull's-eye of Figure 2;

Figure 4 shows another modified form of the bulls-eye of Figure 2;

Figure 5 is a perspective view of a pair of separately adjustable telescopes for positioning adjacent the eyepiece end of the binoculars and aligning therewith.

In further detail the apparatus comprises a firm base plate or pedestal I preferably of heavy metal and provided with a vertical bolting plate or flange 2 having a planed or accurately finished fiat outer surface 3, and at a directionally opposite point on the base plate are a pair of vertically disposed bosses 4 with outer surfaces 4' also planed or finished in exactparallelisn; with the surface 3 of plate 2, and to which bosses 4 a perfectly fiat parallel sided plate 5 (see Figure 5) is adapted to be secured as by thumb screws passing through holes 6 of plate 5 and engaging threaded holes I in the lugs.

Base plate I is preferably supported on a bench table, or tripod not shown, so as to bring it to convenient height for the operator to sight through the binoculars to be adjusted, and spaced a short distance above the upper surface 8 of the base i is a horizontally extending plate or table 9 pivoted at ID on a horizontal axis to a pair of lugs ll extending from the rear side of plate 3, so that table 9 may be tilted up and down with respect to base plate I. The amount of tilting of table 9 is controlled by a thumbscrew l2 threaded through the rear margin of table 9 and impinging upon base plate I below.

Pivoted to and rotatably mounted on tilting table 9 is a circular plate l3 to the upper side of which a vise I4 is secured so as to rotate with plate l3 about a vertical axis, and the rotation of plate l3 and its vise I4 is controlled by a thumbscrew l5 which is rotatably mounted in plate 9 and provided with a pinion gear l6 engaging the teeth I! of an arcuate rack secured to or formed on the edge of plate l3.

Vise I4 is of conventional construction and is provided with a movable jaw l4 operated by a thumbscrew l8, and so positioned on plate I3 as to bring the hinge joint 19 of an average pair of binoculars about central with respect to flange 2 when one of the binocular barrels is gripped between the vise jaws.

The jaws are preferably faced with soft rubber 20 and in Figure 1 are shown as gripping one prism housing 2| of a pair of prism binoculars 22, and with the other prism housing 2|, object glass end 23 and eyepiece 24 free to swing laterally on axis 25 of hinge joint 19.

In Figure 1 the binoculars are shown with prism cover plates removed, so as to expose the two sets of prisms of each barrel or housing, one set of the prisms being indicated at 26 and the other set being equally accessible through the forward open end of the housing at 21, and which prisms are generally movable in various directions for adjusting to alignment under tension of a bowed flat spring 28 which holds them to adjusted position until fixed in place as by a drop of cement applied to their margins.

When a pair of binoculars is clamped in the vise [4 as indicated, its free barrel is free to swing on axis 25 so as to swing the axis of its object glass from 29 to 30 alongthe dotted arcuate line 3 I, the

limit or extent of this movement varying with the size and make of the particular binoculars.

Two small telescopes or collimator tubes 32, 33 are provided for respectively aligning with the axis of the free barrel at the opposite ends of its swinging movement. The main tubes of these telescopes are rigidly mounted, each on the upper end of a perfectly flat slotted bar or arm 34, 35, so as to project at right angles therefrom, and each bar is individually clamped to the planed outer face 3 of flange 2 as by a large thumbscrew 36 passing through the slot 31 of the bar and into a threaded hole 38 in flange 2. This permits either arm to be raised or lowered or swiveled about its thumbscrew so as to adjust the two telescopes to any desired distance apart or height to exactly meet the axis of the free'barrel of the binocular when swung on its pivot 25 from one extreme to the other.

The outer sections 32, 33 of each telescope are revolvable under gentle friction in the main tube and each carries a diaphragm ring 39, 40 fitted with bulls-eye and cross line to be later described, and also provided with a level or bubble glass 4|, 4|, for accurately determining when the'cross lines of the diaphragm or bulls-eye are horizontal and vertical.

The bulls-eye diaphragms may be engraved on a sheet of optical glass centrally fitted within the rings 39, 40, and preferably take the form shown in Figure 2, wherein a plurality of concentric circles 42 are shown, each numbered at four points of the circle and crossed by a vertical 43 and horizontal 44 line or hair line. While Figure 2 shows thepreferred form of the bulls-eye diaphragm and its cross hair lines, other forms may be used, as the bulls-eye lines instead of being circular may be hexagonal as shown'in Figure 3 at 42', or mere spaced dots may be used on the cross hair lines 43 and 44 as shown at 42" in Figure 4, in all cases the lines or dots of the four or several radii being equidistant from the crossing of the hair lines and preferably consecutively numbered as shown in all three figures to facilitate centering of the bulls-eye in the field. The reason for the bulls-eye arrangement of lines or marks will later be explained.

A similar pair of telescopes is arranged for adjustably securing to plate 5 which secures to lugs 4 at the rear of the binoculars to be tested. These telescopes are shown inFigure 5 at 45, 46, each rigidly secured to fiat slotted arms 41, 48 as described-for the forward telescopes, and the slotted arms each independently secured to plate 5 by thumbscrews 49,50 passing through the slots 5|, 52 of the arms. By this means the telescopes 45, 46 may be independently adjusted up and down on plate 5 as well as spaced any required distance. Plate 5 is perfectly fiat and of even thickness and is rigidly secured to the finished surfaces of lugs 4 as by thumbscrews or cap screws not shown, and will there occupy the dotted position shown in Figure 1.

The rear telescopes 45, 46 each have the usual objective at their forward ends 53, 53 and eyepiece at the rear ends 54, 54, and are provided with a cross line inside at the focal points 55, 55' of the eyepieces, and may be turned plumb by turning the eyepieces and also may have bubble glasses mounted on them if desired as in the front telescopes for centering with the cross lines thereof.

In using the apparatus for correcting misalignment of the optical systems in prism binoculars, either the forward or rearward prisms may have shifted, or gotten slightly twisted, though other- Wise centered, or in binoculars where the prisms are rigidly fixed there is an eccentric adjustment of the objective lens which may have become displaced, and any of which errors must be corrected to bring both eye images into coincidence and obtain the stereoscopic effect. The shifting of either prism will cause lateral or vertical relative displacement of the images, while a slight twisting will cause the vertical lines as of a building, and the horizontal lines, as of a roof, to vary so much in the two barrels as to prevent their joining in the eyes as a single image.

To correct the trouble, the prism covers are removed, the binoculars clamped in the vise as shown in Figure 1, the forward telescopes 32, 33 spaced to be in line with the free barrel of the binoculars when swung back and forth on its pivot joint l9, their bull's-eye cross lines are accurately leveled with the bubble glass mounts, then with the free barrel of the binoculars aligned as accurately as possible with one of the telescopessay 32'-by looking through the eyepiece of the free barrel (with telescopes directed to a source of diffused light) and manipulating screws l2 and I5 until the bulls-eye rings are centered in the field of the eyepiece. As the field of binoculars of different powers and sizes varies considerably, the numbering of the bull's-eye rings as shown in Figure 2 gives a ready means of being certain that the largest ring in the field is the same ring all around the field, or in the case of a target as in Figure 4, that the same numbered dots are adjacent the circular margin of the field.

. After the barrel has been thus centered with respect to one of the telescopes, it is swung on its hinge l9 to the other telescope and if found also to show the bulls-eye rings perfectly centered with the field of view and the cross lines vertically and horizontally disposed, the optical system of that barrel could be considered perfect.

If, however, as usually the case, when the free barrel is swung to the second telescope the bullseye is found considerably displaced in the fieldeither to the right, left, up or down, or the cross lines noticeably out of plumb or level, then an adjustment of the prisms is made until about half of the apparent errors are overcome/and after which the thumbscrews I2 and I4 are again manipulated until the bull's-eye rings are centered in the field of view. After this the free barrel is again swung over to the first position and upon sighting through the eyepiece will show a displacement of the bulls-eye rings of about half the former displacement. This is corrected to about half its apparent value by shifting or turning of the prisms, as may be required, then the screws I2, l5 are again manipulated to center the target in the field, and the barrel swung over again to the second position, and the same adjustment to correct'half of the apparent error repeated as described.

By repeating the above several times the apparent errors rapidly diminish until the bullseye rings exactly center themselves in both positions and with the cross lines plumb and level, though for alternate checking, the two rear telescopes 45, 46 may be mounted in place and sighted through in both positions to insure absolute centering of the cross lines in both positions.

After thus adjusting the prisms and/or lens systems of the free barrel, it may be relied on that the axis of its optical system is in line with 75.

the mechanical axis of hinge joint IS. The binoculars are then removed from the vise, the corrected barrel clamped in place, and the same back and forth adjustments carried out on the other barrel until there is no displacement from perfect centering in either position when viewing the target through the eyepiece of the binocular or through the rear telescopes 45, 46, and the cross lines are plumb and level. The adjusted glasses of the barrels are then permanently secured in the adjusted position, as by cement or other means, the covers are replaced on the prism tubes, and the binoculars will be found in perfect alignment.

As previously suggested, in such binoculars as are provided with eccentric or laterally movable mounts of the objectives and/or prisms, which sometimes are provided with adjusting screws, these are suitably adjusted in the aligning operations described above, and require no further fast-ening.

A point to be noted is that the bulls-eye diaphragms in the telescope rings 39 and 40 should be accurately centered with relation to the optical axis of the telescopes, and the mountings may if desired include any suitable means for vertical and horizontal adjustment from the outside to facilitate such centering.

Having thus described my invention and the preferred manner of its use, it will be evident to anyone skilled in the art that various modifications in the structure may be made within the spirit of the invention and scope of the appended claims.

I therefore claim:

1. Apparatus for aligning the optical systems of jointed binocular field glasses comprising a pedestal provided with a vertical flange, a table pivotally mounted on said pedestal for vertical tilting and provided with means for adjusting it to various degrees of tilting, a plate mounted on said table for rotation about an upright axis, and provided with means for adjusting it to any desired degree of rotation, a vise carried by said plate adapted for clamping one barrel of a bin ocular field glass with the other barrel free to swing, and a pair of collimator tubes adjustably secured to said vertical flange adapted respectively for aligning with the optical axis of said free barrel in two positions of swinging.

2. In apparatus as specified in claim 1, a second pair of collimator tubes spaced from the first pair with binoculars positioned between them, and means for individually adjusting the second pair of tubes to respectively align with an extension of the optical axis of said free barrel in its two positions of swinging.

3. The method of aligning the optical systems in a pair of hingedly connected prism binoculars which comprises firmly holding one of the barrels with the other free to swing on its hinge joint, alternately swinging the free barrel from one to the other axis of a pair of spaced collimators while successively shifting the prism of the barrel until a centering target of each collimator shows no apparent displacement when viewed in either position through the eyepiece of the free barrel, thereafter repeating the above operations on the prism. of the other barrel, and securing the prisms in place, to thereby bring the optical axes of both barrels parallel to the axis of the hinged connection of the barrels.

I 4. Apparatus for aligning the optical systems .of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, and a target centered in each of said telescopes adapted for optically centering of its image in the field of view of the eyepiece of the free barrel of said binoculars.

5. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, and a target composed of concentric figures centered in each of said telescopes of a form adapted for optically centering of its image in the field of view of the eyepiece of the free barrel of said binoculars.

6. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in opposite positions of displacement upon swinging the barrel, and a target composed of concentric figures and a pair of cross lines centered in each of said telescopes, said concentric figures being of a form adapted for optically centering of its image in the field of view of eyepiece of the free barrel of said binoculars.

'7. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis,

and means for securing said telescopes in ad- 0 justed position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, a target carried by and centered in each of said telescopes including a straight line and adapted for optically centering of its image in the field of the eyepiece oi the free barrel of said binoculars, means mounting said targets for axial rotation with respect to the body of the telescopes respectively, and means carried by the telescopes for indicating the leveling of said targets in fixed relation to any straight line thereon.

8. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, a target carried by a section of and. centered in each of said telescopes adapted for optically centering of its image in the field of the eyepiece of the free barrel of said binoculars and including a straight line, means providing for axial turning of the sections of said telescopes carrying the centering targets, and a leveling glass secured to each of said sections extending transversely of its axis.

9. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, and a target centered in each of said telescopes adapted for optically centering of its image in the field of View of the eyepiece of the free barrel of said binoculars, each of said telescopes provided with an arm extending at right angles to the longitudinal axis of the telescope, a flat rigid surface against which said arms are adapted to be clamped, and means for adjustably clamping said arms respectively against said surface.

10. In the construction as specified in claim 4, a second pair of telescopes spaced from said first pair of telescopes and between which the binocu-- lars are positioned, and means adapting said second pair of telescopes to be separately aligned respectively with the opposite positions of said axis as extended through the eyepiece of said free barrel, and means for clamping said second pair of telescopes in such aligned position.

11. Apparatus for aligning the optical systems of jointed binocular field glasses comprising means for clamping one barrel of the binoculars with the other free to swing for bodily displacement of its longitudinal optical axis, a pair of telescopes supported for independent bodily movement in a plane at right angles to said axis, and means for securing said telescopes in adjusted position for aligning with said axis respectively in its opposite positions of displacement upon swinging of the barrel, and a target centered in each of said telescopes adapted for optically centering of its image in the field of view of the eyepiece of the free barrel of said binoculars, a second pair of telescopes spaced from said first pair of telescopes and between which the binoculars are positioned, and means adapting said second pair of telescopes to be separately aligned respectively with the opposite positions of said axis as extended through the eyepiece of said free barrel, said last mentioned means including an arm extending at right angles from each telescope, a flat rigid surface against which said arms are adapted to be clamped, and means for adjustably clamping said arms respectively against said surface.

WILLIAM O. HAMMER. 

